Search Results (1,360)

Monoacylglycerols (MAGs) are significant intermediate byproducts in the hydrolysis of oils and fats. The accumulation of MAGs not only reduces the quality and purity of the final products in biodiesel production and edible oil refining but also poses challenges for downstream separation processes. Therefore, the development of efficient biocatalysts for the specific MAG conversion is of great industrial importance. The lipase from Aspergillus oryzae (AOL) has shown potential for lipid modification; however, the wild-type enzyme (WT) suffers from poor solubility, tendency to aggregate, and low specific activity towards MAGs in aqueous systems, which severely restricts its practical application. In this study, a combinatorial protein engineering strategy was employed to overcome these limitations. We integrated fusion protein technology with rational design to enhance both the functional expression and catalytic efficiency of AOL. Firstly, the superfolder green fluorescent protein (sfGFP) was fused to the N-terminus of AOL. The results indicated that the sfGFP fusion tag significantly improved the solubility and stability of the enzyme, preventing the formation of inclusion bodies. The fusion protein sfGFP-AOL exhibited a MAG conversion rate of approximately 65%, confirming the positive impact of the fusion tag on enzyme developability. To further boost catalytic performance, site-directed mutagenesis was performed based on structural analysis. Among the variants, the mutant sfGFP-Y92Q emerged as the most potent candidate. In the MAG conversion, sfGFP-Y92Q achieved a conversion rate of 98%, which was not only significantly higher than that of sfGFP-AOL but also outperformed the widely used commercial immobilized lipase, Novozym 435 (~54%). Structural modeling and docking analysis revealed that the Y92Q mutation optimized the geometry of the active site. The substitution of Tyrosine with Glutamine at position 92 likely enlarged the substrate-binding pocket and altered the local electrostatic environment, thereby relieving steric hindrance and facilitating the access of the bulky MAG substrate to the catalytic center. In conclusion, this work demonstrates that the synergistic application of sfGFP fusion and rational point mutation (Y92Q) can dramatically transform the catalytic properties of AOL. The engineered sfGFP-Y92Q variant serves as a robust and highly efficient biocatalyst for MAG degradation. Its superior performance compared to commercial standards suggests immense potential for cost-effective applications in the bio-manufacturing of high-purity fatty acids and biodiesel, offering a greener alternative to traditional chemical processes. Full article

The optimization of historic district form, given the coordinated relationship between global urbanization and sustainable development, faces the core contradiction between preservation and development. Taking Shenyang’s Nanshi area as a case study, this study aimed to construct a sustainable urban form evaluation system comprising 7 dimensions and 23 indicators by integrating multi-source geographic Big Data. A combination of a weighting approach in rank-order analysis and the entropy weight method was adopted, followed by spatial quantitative analysis conducted based on ArcGIS. The results showed that the sustainability of the area exhibited significant spatial differentiation: historic blocks became high-value areas due to their “small blocks, dense road network” fabric and high functional mix. However, newly built residential areas were low-value zones, constrained by factors such as fragmented green spaces, single-functional land use, and other limitations. Road network density and functional mixing were identified as the primary driving factors, while green coverage rate served as a secondary factor. Based on these findings, a three-tier “element–structure–system” optimization strategy was proposed, providing quantitative decision support for the low-carbon renewal of high-density historic urban districts. Full article

Due to increasing human activities underwater, there is a growing demand for high-speed underwater optical communication (UOWC) data links for security surveillance, environmental monitoring, pipeline inspection, and other applications. Line-of-sight communication is impossible under certain conditions due to misalignment, physical obstructions, irregular usage, and difficulty adjusting the receiver orientation, especially when used in environments with mobile users or submerged sensor networks. Therefore, non-line-of-sight (NLOS) optical communication is used in this study. Advanced modulation schemes—quadrature amplitude modulation and orthogonal frequency-division multiplexing (QAM-OFDM)—were used to transmit the signal underwater between two network nodes. QAM increases the data transfer rate, while OFDM reduces dispersion and inter-symbol interference (ISI). The proposed UOWC system is investigated using a 532 nm green laser diode (LD). Reliable high-speed data transmission of up to 15 Gbps is achieved over horizontal distances of 134 m, 43 m, 21 m, and 5 m in four different aquatic environments—pure water (PW), clear ocean (CLO), coastal ocean (COO), and harbor II (HarII), respectively. The system achieves effectively error-free performance within the simulation duration (BER < 10⁻⁹), with a received optical signal power of approximately −41.5 dBm. Clear constellation patterns and low BER values are observed, confirming the robustness of the proposed architecture. Despite the limitations imposed by non-line-of-sight (NLOS) communication and the diversity aquatic environments, our proposed architecture excels at underwater long-distance data transmission at high speeds. Full article

Background: Ultra-widefield (UWF) images are frequently used for fundus examinations during medical screening. Optos^® generates pseudo-color images using only red and green lasers, which may reduce the visibility of retinal interface lesions. In contrast, Clarus™ incorporates blue light, suggesting potential superiority in epiretinal membrane (ERM) detection. Methods: This retrospective study included 233 patients (408 eyes; 816 UWF images per device) who underwent simultaneous Optos^® and Clarus™ imaging plus optical coherence tomography (OCT) at our institution from March to April 2019. Ten blinded ophthalmologists assessed only the UWF images for ERM presence or absence. Diagnosis was confirmed by fundus examination and OCT. McNemar’s test compared detection accuracy. Results: Clarus™ consistently outperformed Optos^®, with superior sensitivity [median 49% (range 42–70) vs. 14% (4–47); p = 0.002], correct judgment rate [85% (82–90) vs. 78% (44–88); p = 0.010], and lower unassessed rate [6% (2–13) vs. 13% (3–52); p = 0.002]. This superiority held across ERM stages, lens status, and ophthalmologist experience levels. Conclusions: This study demonstrated that Clarus™ significantly outperformed Optos^® in ERM detection accuracy. These results suggest that true-color UWF systems like Clarus™ may be more useful for macular screening in routine practice and health examinations. Full article

The non-thermal plasma-driven cascade process for CO₂-to-methanol conversion shows significant potential in the field of green methanol synthesis. This process innovatively couples a plasma activation module with a catalytic synthesis module via a multi-stage pressurization device, establishing an efficient two-step pathway that converts CO₂ into methanol via a CO intermediate. Such an arrangement establishes an energy conversion system characterized by both low carbon emissions and high efficiency. This work involved an initial technical evaluation employing a custom-built, lab-scale apparatus. The optimum parameters determined through this assessment were a plasma input voltage of 40 V combined with a subsequent reaction temperature of 240 °C. Operation at these specified parameters yielded a CO₂ conversion of 48%, with the methanol selectivity and production rate reaching 40% and 502 g_MeOH${·\mathrm{kg}}_{\mathrm{cat}}^{-1}$·h⁻¹, respectively. Furthermore, industrial-scale process design and scale-up were performed, accompanied by process simulation using Aspen Plus and a subsequent techno-economic evaluation. The results indicate that, compared to the conventional direct CO₂ hydrogenation process, the proposed cascade route can reduce the capital investment by approximately 17%. Full article

Although greenhouse gas emissions have significantly reduced, the European Union still faces a major challenge in meeting its 2050 net-zero goal set under the European Green Deal. Focusing on the impacts of population, economic output, and carbon intensity of economy, this study employs Index Decomposition Analysis to estimate the reductions in carbon intensity needed to reach this target. The findings show that the extent of the technical effort required for decarbonization is much influenced by economic expansion. Under a 3% annual Gross Domestic Product growth scenario, the EU’s carbon intensity of economy must decline by 11.8% per year, which is a particularly demanding rate given the already low baseline. The decomposition also quantifies the technological challenge: under high growth, up to 5867 MtCO₂ in reductions would be needed by 2050 (compared with 1990), with Carbon Capture and Storage (CCS) contributing only 10–15%. In contrast, in zero- or negative-growth scenarios, required reductions fall to 4923–4594 MtCO₂, with CCS accounting for up to 50–90%. These results show that decarbonization in EU industrial sectors requires systemic transformations and strategic CCS deployment. A balanced approach, limiting economic growth and increasing innovation, appears essential to achieve the climate neutrality target. Full article

Rapid economic growth has directly driven up energy demand, and the gradual depletion of traditional fossil fuels has severely hindered sustainable development. Developing green and efficient geothermal exploitation technologies constitutes a crucial measure for tackling this sustainable development issue. This paper presents a field test associated with a clean energy system conducted in the Guanzhong Basin, China, with the core component of a coaxial casing deep geothermal well. A distributed temperature sensing system (DTS system) with over 3000 m-depth optical fiber installed and adopted to monitor near-wellbore formation temperature changes. Combining information on the inlet/outlet water temperature and flow rate monitored by an integrated temperature–pressure monitoring system, the heat transfer patterns during the operation of the deep geothermal well are deeply investigated. The research results demonstrate that a higher operation parameter of flow rates has a significant increasing effect on the heat transfer capacity of heat exchangers for coaxial casing deep geothermal wells. Although the increase in inlet temperature has minimal effect on the outlet temperature, it leads to a continuous decline in heat transfer capacity. In addition, as heat exchange duration extends, the geothermal gradient of the near-wellbore formation progressively declines. Full article

Japan has largely achieved the “first half” of SDG 6—universal access to safe drinking water and sanitation—through decades of intensive investment in water supply and sewerage systems, implementation of the Total Pollutant Load Control System, and stringent regulation of industrial effluents. National indicators show that coverage of safely managed drinking water and sanitation services is nearly 99%, and domestic statistics report high compliance rates for BOD/COD-based environmental standards in rivers, lakes, and coastal waters. Conversely, the “second half” of SDG 6 reveals persistent gaps: ambient water quality (6.3.2) remains at 57% (2023 data), while water stress (6.4.2) is at approximately 21.6%. Furthermore, SDG 6.6.1 shows that 3% of water basins are experiencing rapid changes in surface water area (2020 data), with ecosystems increasingly threatened by hypoxia in enclosed bays and climate-induced vulnerabilities. Drawing on global comparisons, this review synthesizes Japan’s progress toward SDG 6, elucidates the structural drivers for remaining gaps, and proposes policy pathways for a nature-positive water future. Using national statistics (1970–2023) and the DPSIR framework, our analysis confirms that improvements in BOD/COD compliance plateaued around 2002, reinforcing concerns that point-source measures alone are insufficient to address diffuse pollution, groundwater nitrate contamination, and emerging contaminants like PFAS. We propose six strategic directions: (1) climate-resilient water systems leveraging groundwater; (2) smart infrastructure renewal; (3) advanced treatment for emerging contaminants; (4) basin-scale IWRM enhancing transboundary cooperation; (5) data transparency and citizen engagement; and (6) scaled nature-based solutions (NbS) integrated with green–gray infrastructure. The paper concludes by outlining priorities to close the gaps in SDG 6.3 and 6.6, advancing Japan toward a sustainable, nature-positive water cycle. Full article

In recent years, interest in carbon dioxide (CO₂) hydrogenation technologies has intensified. Driven by the continuous rise in greenhouse gas emissions and the unprecedented negative impacts of global warming, these technologies offer a viable pathway toward sustainability and support the development of low-carbon industrial processes. In addition to methanol and methane, other possible hydrogenation products (i.e., hydrocarbons, formic acid, acetic acid, dimethyl ether, and dimethyl carbonate) are of industrial relevance due to their wide range of applications. Therefore, this review aims to provide a comprehensive overview of the various aspects associated with thermocatalytic CO₂ hydrogenation processes, from thermodynamic and kinetic studies to upscaled reactor modeling and process synthesis and optimization. The review proceeds to examine different integration strategies and optimization approaches for multi-product systems, with the objective of evaluating how distinct technologies may be combined in an integrated flowsheet. It then concludes by outlining future research opportunities in this field, particularly those related to developing comprehensive kinetic rate expressions and reactor modeling studies for routes with low technology readiness levels, the exploration of prospective reaction pathways, strategies to mitigate the dependence on green hydrogen (which, today, exhibits high costs), and the consideration of market price or product demand fluctuations in optimization studies. Overall, this review provides a solid base to support other decarbonization studies focused on hydrogenation technologies. Full article

Agricultural soils are the largest anthropogenic source of nitrous oxide (N₂O), primarily due to excessive nitrogen (N) fertilization and inefficient N management. Mitigating N₂O emissions from croplands without compromising productivity is therefore a major global challenge for climate and environmental sustainability. A three-year split-plot field experiment was conducted in an arid maize production region of northwestern China to examine how green manure intercropping combined with reduced chemical N input regulates N₂O emissions and soil N residues. The main plots comprised maize monoculture (M), maize intercropped with common vetch (M/V), and maize intercropped with rape (M/R), while subplots consisted of local conventional N application (N1: 360 kg N ha⁻¹) and a 25% reduced rate (N2: 270 kg N ha⁻¹). Results indicated that intercropping with green manure can offset the reduction in maize grain yield caused by a 25% decrease in N supply. Green manure intercropping significantly decreased cumulative N₂O emissions compared with monoculture maize, and the mitigation effect was further strengthened under reduced N input. The M/V system under reduced N input exhibited the strongest mitigation effect, reducing N₂O emissions per unit of grain yield by 9.2–11.5% compared with the M/R system. This reduction was driven by the ability of M/V to stabilize soil mineral N availability. Notably, the independent maize growth stage contributed 52.6–66.9% of total seasonal N₂O emissions, emphasizing it as a critical period for emission mitigation. Overall, integrating green manure intercropping with reduced chemical N input effectively mitigates N₂O emissions while maintaining maize productivity in arid regions, providing a practical strategy for sustainable and environmentally responsible agricultural intensification. Full article

In view of the technical bottleneck of microbial dynamic monitoring during the solid-state fermentation of traditional Baijiu, this study introduced green fluorescent protein (GFP) labeling technology into the dominant Saccharomyces cerevisiae of Jiang-flavored Baijiu to construct the chromosomal integration engineering strain named FSC01. By designing an integrated recombinant plasmid containing the GFP gene and the geneticmycin resistance gene, an engineered strain that stably expresses fluorescent proteins was obtained by electroconversion. Flow cytometry verification showed that FSC01 showed excellent linear responses in the pure microbial system (R² = 0.998) and the complex matrix of Baijiu jiupei (R² = 0.981), with a detection limit of 10² cells/mL, and the detection cycle was shortened to 10 min. Solid-state fermentation simulation experiments show that the inoculation volume of FSC01 of 10⁵ cells/kg can not only ensure the effective identification of fluorescence signals, but also does not significantly interfere with the growth and growth patterns of the original yeast (p > 0.05), which is highly consistent with the results of the traditional plate counting method. Dynamic monitoring shows that Saccharomyces cerevisiae during fermentation presents a typical succession pattern of “increase first and then decrease”, reaching a peak on the 7th day (1.2 × 10⁷ cells/g), which is positively correlated with the base alcohol yield rate (26.7%). Compared with metagenomic (72 h) and PMA-qPCR (4 h) methods, this technology breaks through the limitations of specificity and timeliness of live bacteria detection, and provides a single-cell-level dynamic analysis tool for the digitization of traditional brewing processes. In the future, it will be expanded to monitor key functional microorganisms such as lactic acid bacteria through a multi-color fluorescent labeling system, and optimized pretreatment to eliminate starch granule interference, and promote the in-depth application of synthetic biology technology in the traditional fermentation industry. Full article

The rapid evolution of wireless communication toward Fifth Generation (5G) networks has enabled unprecedented performance improvement in terms of data rate, latency, reliability, sustainability, and connectivity. Recent years have witnessed an excessive deployment of new 5G networks worldwide. This deployment lead to an exponential growth in traffic flow and a massive number of connected devices requiring a new generation of energy-hungry base stations (BSs). This results in increased power consumption, higher operational costs, and greater environmental impact, making energy efficiency (EE) a critical research challenge. This paper presents a comprehensive survey of EE optimization strategies in 5G networks. It reviews the transition from traditional methods such as resources allocation, energy harvesting, BS sleep modes, and power control to modern artificial intelligence (AI)-driven solutions employing machine learning, deep reinforcement learning, and self-organizing networks (SON). Comparative analyses highlight the trade-offs between energy savings, network performance, and implementation complexity. Finally, the paper outlines key open issues and future directions toward sustainable 5G and beyond-5G (B5G/Sixth Generation (6G)) systems, emphasizing explainable AI, zero-energy communications, and holistic green network design. Full article

This study investigates the feasibility of absolute decoupling—where economies expand while CO₂ (Carbon Dioxide) emissions decline in absolute terms—by identifying its key macro–energy drivers across 79 countries (2000–2025). We construct a comprehensive panel of energy-system indicators and estimate the probability of decoupling using two complementary classifiers: a penalized logistic regression and a gradient-boosted decision tree model (GBM). The non-parametric GBM significantly outperforms the linear baseline (ROC–AUC ~0.80 vs. 0.67), revealing complex non-linearities in the transition process. Explainable AI analysis (SHAP) demonstrates that decoupling is not driven by GDP growth rates alone, but primarily by sharp reductions in energy intensity and the active displacement of fossil fuels. Crucially, our results indicate that increasing renewable capacity is insufficient for absolute decoupling if the fossil fuel share does not simultaneously decline. These findings challenge passive “green growth” narratives, suggesting that current policies are inadequate; achieving climate targets requires targeted mechanisms for active fossil fuel phase-out rather than merely relying on renewable additions or economic modernization. Full article

Currently, with the widespread popularization of e-commerce systems, enterprises have increasingly high requirements for the timeliness of order fulfillment. It has become particularly critical to enhance the operational efficiency of heterogeneous robotic “goods-to-person” (G2P) systems in book e-commerce fulfillment, reduce enterprise operational costs, and achieve highly efficient, low-carbon, and sustainable warehouse management. Therefore, this study focuses on determining the optimal storage location assignment strategy and order batching method. By comprehensively considering the characteristics of book e-commerce, such as small-batch, high-frequency orders and diverse SKU requirements, as well as existing system issues including uncoordinated storage assignment and order processing, and differences in the operational efficiency of heterogeneous robots, this study proposes a joint optimization framework for storage location assignment and order batching centered on a multi-objective model. The framework integrates the time costs of robot picking operations, SKU turnover rates, and inter-commodity correlations, introduces the STCSPBC storage strategy to optimize storage location assignment, and designs the SA-ANS algorithm to solve the storage assignment problem. Meanwhile, order batching optimization is based on dynamic inventory data, and the S-O Greedy algorithm is adopted to find solutions with lower picking costs. This achieves the joint optimization of storage location assignment and order batching, improves the system’s picking efficiency, reduces operational costs, and realizes green and sustainable management. Finally, validation via a spatiotemporal network model shows that the proposed joint optimization framework outperforms existing benchmark methods, achieving a 45.73% improvement in average order hit rate, a 48.79% reduction in total movement distance, a 46.59% decrease in operation time, and a 24.04% reduction in conflict frequency. Full article

Cabbage (Brassica oleracea L. var. capitata) is an important leafy vegetable crop, and the development of homozygous parental lines is essential for F₁ hybrid breeding. Isolated microspore culture (IMC) provides a rapid approach for producing haploid and doubled haploid (DH) lines. However, its efficiency in cabbage remains highly dependent on genotype, donor plant growth conditions, and culture conditions. This study aimed to optimize key factors affecting microspore embryogenesis and plant regeneration in a Korean green cabbage (‘SJ-Ca 13’) and to evaluate the ploidy and genetic characteristics of regenerated plants. Microspore yield and embryogenesis were strongly influenced by flower bud size. Bud size of 4.0 ± 0.5 mm yielded the highest number of microspores (4.17 × 10⁴ per bud) and exclusively produced microspore-derived embryos (2.33 embryos per Petri dish), whereas smaller or larger buds failed to induce embryogenesis. Heat shock treatment at 32.5 °C was essential for embryogenesis, with 24 or 48 h of treatment inducing embryo formation, while prolonged exposure (72 h) completely inhibited embryogenesis. Efficient shoot regeneration was achieved when microspore-derived embryos were cultured on semi-solid MS medium with reduced salt strength (1/3×) and higher agar concentration (1.0%), resulting in the highest shoot regeneration rate. Ploidy test revealed that 50% of regenerated plants were spontaneous doubled haploids. SSR analysis using 26 markers detected no genetic polymorphism among regenerated plants. Overall, this study establishes an efficient IMC and regeneration system for cabbage and demonstrates its potential for rapid DH line production to support cabbage breeding programs. Full article